Updated docker logs timestamp to RFC3339

Currently the docker logs timestamp flag generates log entries like:

    $ sudo docker logs -ft daemon_dave
    [May 10 13:06:17.934] hello world

It uses Go's StampMilli timestamp to generate the timestamp. The entry
is also wrapped in [ ].

This is non-standard operational timestamp and one that will require
custom parsing.

The new timestamp is RFC3999Nano and generates entries like:

    2014-05-10T17:42:14.999999999Z07:00 hello world

These are readily parsed by tools like ELK.

Docker-DCO-1.1-Signed-off-by: James Turnbull <james@lovedthanlost.net> (github: jamtur01)

Docker-DCO-1.1-Signed-off-by: Tibor Vass <teabee89@gmail.com> (github: tiborvass)
Upstream-commit: aa0eca03e6662c5f6b4f0f47190a45f49b61e357
Component: engine

components/engine/api/client/commands.go

@@ -1616,7 +1616,7 @@ func (cli *DockerCli) CmdEvents(args ...string) error {
 		loc = time.FixedZone(time.Now().Zone())
 	)
 	var setTime = func(key, value string) {
-		format := "2006-01-02 15:04:05 -0700 MST"
+		format := time.RFC3339Nano
 		if len(value) < len(format) {
 			format = format[:len(value)]
 		}